This application relates to polyphthalamide/poly(arylene ether) blends and more particularly to flame retardant polyphthalamide/poly(arylene ether) blends.
Polyphthalamides (PPA) are semi-aromatic, high temperature nylons that typically have melting points higher than 290° C. and glass transitions temperatures greater than 100° C. PPAs are generally based on polyamide 6T. However polyamide 6T has a melting point of 370° C., and therefore is difficult to process and/or blend with other polymers, such as polyphenylene ether (PPE). PPAs generally are copolymers that have various ratios of polyamide 6T, polyamide 6I, and polyamide 6/6 to control properties such as melt flow, melting point, and glass transition temperature.
PPAs and high temperature nylons are widely used in applications that require a very high resistance to heat. Electrical connectors such as those found in computers, cell phones, and flat panel televisions use these polymers extensively. These electrical connector applications also frequently require the material be flame retardant at thicknesses at or below 1.0 millimeter (mm). Flame resistance is difficult to achieve for articles with lower thicknesses while maintaining or improving mechanical properties.
Popular flame retardants for PPAs include halogenated flame retardant systems such as brominated flame retardant systems. However, there is an increasing trend to reduce or halt the use of halogenated flame retardant systems. However, PPAs generally require a large amount of non-halogenated flame retardants to achieve good flame retardant performance. High levels of non-halogenated flame retardants can have a negative impact on overall physical properties. Additionally, given the high temperatures processing temperatures required for PPAs many non-halogenated flame retardants cannot be used due to degradation. Accordingly there remains a need for non-halogenated flame retardant PPA materials with good physical properties.